Update edition to 2021 (#153)

cjrh · web-flow · commit 4ac17da8f660 · 2023-11-19T01:14:37.000+01:00
diff --git a/Cargo.toml b/Cargo.toml
@@ -3,7 +3,7 @@ name = "tantivy"
 version = "0.21.0"
 readme = "README.md"
 authors = ["Damir Jelić <poljar@termina.org.uk>"]
-edition = "2018"
+edition = "2021"
 license = "MIT"
 
 [lib]
